Nairobi , Kenya -LRB- CNN -RRB- -- The U.S. Embassy in Kenya warned it has credible information of an imminent terror attack , days after the east African nation announced it is sending troops to Somalia to battle Islamist militants .

The attack is likely to target places that foreigners congregate in Kenya , including malls and night clubs , the embassy said .

The U.S.Embassy did not offer details on who might carry out such an attack , but said it has taken measures to limit official U.S. government visits . It urged its citizens to consider deferring travel to Kenya .

The warning comes after Kenya sent troops across the border into Somalia to pursue Islamist Al-Shabaab militants . The terror group has threatened Kenya with retaliatory attacks , saying it considers the forces ' incursion an affront to Somalia 's sovereignty .

Al-Shabaab , which is linked to al Qaeda and has been designated a terrorist organization by the United States , is fighting to impose its own interpretation of Islamic law , or sharia , on Somalia .

Kenya has blamed some recent abductions of tourists and aid workers on the terror group , which has heightened tensions .

On September 11 , armed bandits broke into a beachfront cottage where Britons Judith and David Tebbutt , both in their 50s , were staying . David Tebbutt was shot dead while trying to resist the attack . His wife was grabbed and spirited away on a speedboat , and is believed to have been taken into Somalia .

On October 1 , pirates made another cross-border raid , this time snatching a French woman in her 60s , who used a wheelchair and was believed to be in bad health , from a holiday home on Manda Island where she lived part of the year . She later died , likely because of the kidnappers ' refusal to give her medicine , according to the French Foreign Ministry .

Also this month , gunmen abducted two Spanish workers from the medical charity Doctors Without Borders from the Dadaab refugee complex , about 80 kilometers -LRB- about 50 miles -RRB- from the Somali border .

Al-Shabaab has denied responsibility for the abductions .

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The embassy urges citizens to consider deferring travel

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Kenya has sent troops across the border into Somalia to pursue suspected Islamic militants

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Recent abductions of tourists and aid workers in Kenya have heightened tensions